1. Preheat the oven to 180C | 350F. Grease 3x15cm (6in) cake tins with a little butter and line the bottoms with baking paper. Dust with flour and tap out any excess.
2. Put the flour, sugar, spices, baking powder, bicarbonate of soda and salt in the bowl of your stand mixer fitted with the whisk attachment. Mix briefly on low speed, add the cubed butter and mix again until the mixture resembles breadcrumbs.
3. Add the eggs, one at a time, and mix again, scraping the sides of the bowl with a silicone spatula to make sure everything is well blended.

4. Mix the vanilla and buttermilk and then gradually add to the batter, beating on medium speed until it is smooth. Scrape the sides of the bowl as needed.
5. Divide the batter into the prepared tins and bake for 20-25 minutes. The cakes are ready when springy to the touch and a skewer inserted in the centre comes out clean.
6. Transfer to a wire rack to cool slightly and then gently turn the cakes out of the tins. Cool completely before filling.

7. Make the caramel: put the sugar and water in a medium heavy-bottomed pan. Bring to the boil and cook, swirling the pan, until the caramel turns a deep gold. Remove the caramel from the heat and pour in the cream – be careful, this will cause the caramel to bubble and rise in the pan. Add the butter and cinnamon and salt and stir using a balloon whisk.

8. Mix the mascarpone, icing sugar, spices and vanilla on low speed, gradually adding the cream. Increase the speed until you have firm peaks, scraping the down the bottom and sides of the bowl halfway through. Do not over beat as the frosting may curdle. Transfer to a piping bag fitted with a round tip.
9. Pipe the frosting over the bottom cake layer and then drizzle with some caramel. Repeat until you have assembled the cake and then smooth the frosting over the entire cake.

10. Carefully drizzle some caramel around the perimeter of the cake so that it drizzles down the sides. Top with sugar mini doughnuts or pipe any extra frosting on the cake and drizzle with more caramel.